Remove 'Not Started' status from playbook checkpoint

Playbook status should only be reported for phases that have completed
or which have been started.  Reporting 'Not Started' could be confusing
when running playbooks that do not have an 'installer phase'.

Fixes #5675

roles/installer_checkpoint/callback_plugins/installer_checkpoint.py

@@ -159,11 +159,6 @@ class CallbackModule(CallbackBase):
                         self._display.display(
                             '\tThis phase can be restarted by running: {}'.format(
                                 phase_attributes[phase]['playbook']))
-                else:
-                    # Phase was not found in custom stats
-                    self._display.display(
-                        '{}{}: {}'.format(phase_title, ' ' * padding, 'Not Started'),
-                        color=C.COLOR_SKIP)
 
         self._display.display("", screen_only=True)